Food quality monitoring

S. Miertus, J. Katrlik, A. Pizzariello, M. Stred ansky, J. Svitel and J. Svorc, Amperometric biosensors based on solid binding matrices applied in food quality monitoring, Biosens. Bioelectron., 13(7-8) (1998) 911-923. 

The USFDA stipulated a maximum level of contamination of seafood by methylmercury of 1 mg/kg [185]. Consequently, routine speciation analyses had to be implemented in laboratories monitoring the quality of food products before these could be allowed onto the consumer market. The techniques usually used for monitoring food quality are LC coupled with CV AAS or CV ICP MS [172]. The inference to be drawn from van Dael s review [185] is that advanced techniques, such as CV AAS, CV AFS, FT IR and microwave-induced plasma AES (MIP AES), and less sophisticated methods offer comparable selectivity and sensitivity for determining speciation forms of Hg in food to satisfy food quality monitoring requirements. 

MIPS are also popular for the development of mass-sensitive sensors, especially quartz crystal microbalance (QCM). The sensing response is based on the linear relationship between the resonant frequency of the crystal and the mass of the detection system. In this example, MIPs were used to detect the odorant 2-methylisobomeol (MIB), created by microorganisms." The polymer with a cavity specific to MIB template was formed on the QCM surface in situ. The specific recognition depended on the hydrogen bond between the hydroxyl gronp of templates and the carboxylate group of monomers. The detection limit of this sensor was about 200 J,gL This simple and inexpensive method may have potential applications in food quality monitoring of MIB. 

Quality control is intended to monitor and evaluate the performances of both food and human processes that contribute to food quality. The basic principle of this function is the control circle that involves (1) the taking of a process sample by the analysis or measuring unit, (2) determining whether process results meet set tolerances or limits, (3) judging the character and level of any discrepancy, and (4) application of corrective action to adjust the system to an acceptable level (Figure 7.1.1). A distinction is made between measuring and analysis, whereby the first involves direct measurements (e.g., pH, temperature) and the second involves taking samples, sample preparation, and actual analysis. ... 

We have described the CQP concept from a techno-managerial perspective which means that we explicitly pay attention to the roles of both the food and human systems that constitute a food quality management system. The principle beyond the CQP concept is that one need only to control those steps in the process that are critical toward decay of the quality attributes. CQPs must be monitored, documented, and validated in such a way that the system is able to assure a certain quality level. 

In this chapter we have explained several system-inherent factors of organic fruit growing that can improve fruit quality. However, with the intensification of organic fruit production currently under way worldwide (e.g. more intensive nitrogen application on horticultural crops), there is a risk of quality decrease. Therefore, technical progress in organic farming should be closely and scientifically monitored for (side) effects on food quality, possibly in a holistic view that also includes environmental, social and human health criteria. 

There are two main reasons for determining biogenic amines in foods (1) their potential toxicity and (2) the possibility to use them as food quality markers (quality control of raw materials, monitoring fermentation processes, process control, etc.) [281]. 

In addition to the need for scientific improvements to allow probabilistic risk assessments to be properly performed and interpreted, there also exists a need to educate stakeholders about what the US system for tolerance establishment and monitoring does and does not do. In simplest terms, the US system can be described as a food quality system but not necessarily a food safety system. This results from the fact that the pesticide tolerances are not safety standards but rather exist as enforcement tools that allow an assessment of how well pesticide application regulations are adhered to. Violative residues demonstrate the likelihood of pesticide misuse but should not be considered, in the vast majority of cases, to represent unsafe residues. Safety considerations govern whether or not the use of pesticides on specified commodities will be permitted tolerances, when granted, serve as indicators of good agricultural practices rather than as toxicological benchmarks. 

We are working with the Food Quality Control Department of the Ministry of Health to study the contamination of OCPs and PCBs in local fish and chickens. This project is in line with our current effort to assess the health risk arising from consumption of food contaminated with POP chemicals. The health risk assessment of POPs through dietary intakes project involved analyses of OCPs and PCBs in various foodstuff, initially raw materials which will be extended to cooked food. Unfortunately, we do not currently have the capability to analyze PCDD/PCDF in our laboratory but there are two high resolution mass spectrometers in the country that are capable of analyzing PCDD/PCDF. National and international collaborations will definitely improve the country capacity to monitor POPs not only those listed in the Stockholm Convention but other toxic chemicals found in the environment. 

Monitoring of changes of food quality during the storage and processing... 

Monitoring of Changes of Food Quality During the Storage and Processing... 

The use of biosensors for industrial and environmental analysis is very important for the control of food manufacturing processes, for the evaluation of food quality, for the control of fermentation processes and for monitoring of organic pollutants. 

Dresser Instmments of Stratford, CT, under the ebro brand has introduced a handheld instmment called the Food Oil Meter (FOM-200). This instmment can repeatedly measure polar compounds within seconds in hot oil to directly monitor oil quality in a fryer. The results obtained from the FOM-200 correlates within +/- 2% of the official lUPAC method 2.507/DFG method III-3b for polar compounds and can store many characteristic oil curves for reference. The instmment is being used by several researchers in their frying studies and fast food franchises to better schedule filtering aids additions and oil replacements in order to improve overall food quality. 

Food science is the study of the chemistry, microbiology, and processing of foods. Food technicians are responsible for testing foods for quality and acceptability in carefully controlled taste tests. Microbiologists in the food industry monitor the safety of food products. Food analysts work in laboratories to monitor the composition of foods and the presence of pesticides. Some food scientists create new food products or food ingredients, such as artificial sweeteners. 

Internal foreign bodies (i.e., foreign bodies embedded into the food material) are a nightmare for food plant quality monitoring. Detection systems are generally based on analysis by X-rays, the absorbance of which depends on the atomic number and concentration of the material [40]. However, very often the X-rays are not sensitive to intrinsic foreign bodies such as stem, pits, skin pieces or hair. 

Overall, food quality may be considered in terms of taste, textme, mouthfeel and other sensorial attributes or in terms of macro- and micronutrient content. For any concept of visual quality, colour acts as a very useful and intuitive indicator. Colour can be assessed at various times during the lifetime of a food product - from raw materials, e.g., the quality of flour for baking, through processing, e.g., monitoring roasting of coffee beans, and at the end point where a finished product needs to be confirmed as suitable for its designed purpose,... 

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